Thirteen-year-old Jasira Maroun (Summer Bishil) has been going through a bad patch lately. First came the arrival of menstruation (thanks, God), then the discovery of masturbation (no, really, thank you), then (are you still there, God?) a particularly icky episode of statutory rape at the hands — well, the hand — of Mr. Vuoso (Aaron EckhartAaron Eckhart), the creepy dad next door. Jasira is one of life's punching bags at the moment, and life is clearly going for a knockout.

If there were more to this teenage Candide than the sum of the nasty things that are done to her, "Towelhead" might have been as entrancing a movie as "American Beauty," which also examined a grown man's sexual obsession with a young girl. But Alan Ball, who scripted that film and directs from his own script here, seems more concerned with pushing buttons than with any sort of contemplative inquiry; and Jasira is such a passive lump (she has the feisty spirit of a shower towel) that there are times you want to reach out and give her a swat yourself.

The movie opens in 1990, on the eve of the first Gulf War. Jasira is living in Syracuse with her whack-job mother, Gail (Maria BelloMaria Bello), and has just received a nice pubic-hair trim from her mom's skeezy live-in boyfriend. Gail blows up when she learns about this, angry not with the boyfriend but with Jasira herself, whom she berates as an unknowing temptress. So the girl is dispatched to Houston to live with her Lebanese father, Rifat (the excellent Peter Macdissi), a cold, pompous prig who works for NASA and is quick to take offense with anyone who mistakes him for a Muslim Arab when in fact he's a Christian and can't wait for U.S. forces to invade Iraq and kick Saddam Hussein's butt.

Rifat is every girl's nightmare dad. He flips out when Jasira fails to wear a bra under a T-shirt, is infuriated by her desire to buy tampons and appalled by her friendship with a new schoolmate named Thomas (Eugene Jones) — not because Thomas is black, of course, but because of what her connection to him might do to her "reputation." Jasira manages to get away from her father's judgmental glowering occasionally to babysit the little Vuoso boy next door, who introduces her to his own father's collection of skin mags. We can tell she finds these exciting because she keeps rubbing her thighs together and, in one of the movie's several cringe-inducing sequences, fantasizes herself as the sexy star of a Playboy-style photo shoot. (Bishil was 18 at the time of filming, but she plays 13 very convincingly.)

Soon enough she meets Mr. Vuoso, and in a scene that might have been guest-directed by Larry Clark, inadvertently loses her virginity to him. Thus awakened, she proceeds to offer herself up to the more age-appropriate Thomas, who's only too happy to be of service. (In the afterglow of their first grapple he asks, "Do you feel like a woman?" Men, what pigs.)

Fortunately, Jasira's other next-door neighbors, the Hines family, are a model of domestic perfection. Husband Gil (Matt Letscher) is a sensitive Peace Corps veteran who happens to speak Arabic (which comes in really handy at a key point in the plot), and pregnant mom Melina (Toni ColletteToni Collette) is a beacon of maternal warmth who's happy to snuggle Jasira in under her capacious wing.

The movie takes as its subject grown-ups' incomprehension of adolescent sexuality, but tells us nothing really new about it — the picture seems rather uncomprehending itself. We're meant to be witnessing a girl's hit-and-miss sexual awakening, but Jasira never seems anything other than half-asleep. The sex scenes aren't visually graphic — not quite — but they have an emotional explicitness which is nearly as disturbing. Unlike "American Beauty," in which Kevin Spacey'sKevin Spacey's lust for a girl in her late teens was at least understandable, Eckhart's fixation on a 13-year-old here — despite the actor's best efforts to illuminate the character's torment — is fundamentally repellent. We want Jasira's sexual travails to stop, and we wish she felt the same way. But she just keeps sticking her chin out for another punch.

Check out everything we've got on "Towelhead."

Don't miss Kurt Loder's review of "Eagle Eye," "Choke" and "The Midnight Meat Train," also new in theaters this week.

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